Module 1 - Psychiatric Pharmacology (Block 4)

Focus on the basics of psychotic disorders for pharmacological treatment.
Recognize the need for an understanding of the symptoms rather than deep expertise.

Psychosis is characterized by two main types of symptoms:
- Positive Symptoms: Additional experiential symptoms added to a person's life, such as hallucinations and delusions.
- Negative Symptoms: Symptoms that create a flattening or withdrawal from everyday experience.

Positive Symptoms do not indicate "good"; they refer to symptoms like:
- Hallucinations: Auditory, visual, or bodily sensations that do not exist in consensus reality.
- Delusions: False beliefs where individuals think they are in situations of power or danger (e.g., paranoia).
Negative Symptoms imply a deficit or lack in function, for example:
- Flat Affect: Reduced emotional expression.
- Social Withdrawal: Avoidance of social interactions or connections.

The nurse may find negative symptoms more observable due to:
- Easier to see someone’s withdrawal or lack of interaction than a person experiencing silent hallucinations or delusions.
Positive symptoms can range from severe agitation to silent auditory hallucinations, making self-harm disclosures ambiguous.

Brain chemistry associated with psychosis still largely unknown;
Key neurotransmitters involved include:
- Dopamine: Dysregulated in various brain areas, linked to positive symptoms.
- Serotonin: Imbalanced levels contribute to psychotic experiences.

Developed in the 1950s and 1960s, major prototype: Haloperidol.
Mechanism: Strong dopamine blockade, effective for schizophrenia and acute agitation.
Adverse Effects:
- Extrapyramidal Symptoms (EPS): Include dystonia, Parkinsonism, akathisia, and tardive dyskinesia (TD).
- Dystonia: Muscle spasms often in the neck; can be treated with benztropine or diphenhydramine.
- Parkinsonism: Shuffling gait; managed similarly to Parkinson’s disease.
- Akathisia: Severe restlessness; might use beta-blockers for management.
- Tardive Dyskinesia: Chronic and often irreversible, progression monitored using the AIMS scale.
- Neuroleptic Malignant Syndrome (NMS): Severe reaction including high fever, rigidity, and autonomic instability, requiring immediate intervention.

Evolved to reduce adverse effects, prototype: Risperidone.
Mechanism: Primarily serotonin antagonists with less dopamine blockade, reducing EPS risk.
Adverse Effects:
- Weight Gain: Significant patient concerns; can cause metabolic syndrome, diabetes, and elevated cholesterol.
- Mild EPS: Possible but significantly reduced.
- Prolactin Elevation: Risk of gynecomastia, an uncommon but notable side effect.
- Certain medications like Clozapine can lead to Agranulocytosis, requiring careful monitoring.

Olanzapine: Often used in palliative care; sedating and can stimulate weight gain.
Quetiapine: Also sedating; some use as a sleep medication, associated with cataracts.
Ziprasidone and Lurasidone: Need to be taken with food for effective absorption.
Aripiprazole: Activating, requiring caution in agitated patients; could exacerbate symptoms if over-stimulated.

Special caution is required when administering antipsychotics to the elderly, especially regarding increasing risks of adverse effects.
Non-pharmacological interventions may help minimize agitation in elderly patients with dementia (e.g., music therapy, maintaining a calm environment).

Key syndromes to monitor include:
- Serotonin Syndrome
- Neuroleptic Malignant Syndrome
- Lithium Toxicity: Due to dehydration-related prerenal kidney issues impeding lithium excretion.
Importance of early detection of adverse effects before they escalate, emphasizing the need for differential diagnoses of symptoms across drug classes.

MAOIs: Risk of hypertensive crisis with tyramine-containing foods, necessitating dietary guidelines.
Clozapine: Watch for infection signs due to low neutrophil counts.
Benzodiazepines: Comparable caution to opioids due to addiction potential and respiratory depression risk.
Understand the need to taper medications rather than stopping abruptly, especially steroids and mood-stabilizing medications like lithium.

Summary of key safety principles, potential overlap in symptoms across disorders, the importance of pharmacodynamics, and prompt identification of toxicity and adverse effects as critical aspects of nursing care in psychotic disorders.